North Korea has hit back, posting interviews with family members where they plead for their loved ones to return, warning that they will face brainwashing if they stay in South Korea.

As one distraught mother spoke to the camera, the teenage girl sat quietly holding her hand, but as soon as her mother finished the girl made an urgent appeal. "Father I miss you. Please come back now," she cried. The girl's father is Hong Yong-hak, a 44-year-old North Korean who is among the would-be defectors.

"They make the ridiculous claim that my daughter's defecting," said another woman, who says she is the mother of 22-year old Pak Myong-ok.

The mother of 21-year-old nurse Bong Un-ha says it is all a conspiracy. "How would Un-ha ever fall to brainwashing by the enemy?" she said.

Of the 31, 27 North Koreans who want to come home were taken to the heavily fortified border by South Korean authorities last week. But officials from the North refused to take them back until the other four were returned as well.

Seoul says the two men and two women have chosen to stay of their own free will, but Pyongyang is not backing down.